Now that more players have broken through and completed mission X, it is time to explain the new Armor Mod option that can be accessed at the Select Heli screen.
Whenever a Cat Type has this option (by beating mission X with that Cat regardless of continues), players can increase the amount of starting armor by 1 for every USER credit in stock by pressing up. This is the secondary function of those USER credits that have been accumulating. Why is this useful? 1 credit for 1 armor is much more expensive than continuing which gives 3 armor instead, but this armor boost qualifies for all criteria requiring a 1CC (one credit clear), including achievements and entry into mission 9! This is known as an "Assisted 1CC".
How does this work? For example, assuming a USER credit stock of 50, if a player knows that it takes on average around 10 continues to beat mission X, that equals 10 x 3 = 30 additional armor to do it with the Assisted 1CC. Simply increase the armor during the Select Heli screen until it reads 33. Mods can only go as high as there are USER credits. In Team play, both players share the same USER credits pool.
However, what if the game goes wrong and the player runs out of armor before mission X? Continuing will start with the default 3 armor and the 1CC is no longer valid. Perhaps using another 10 USER credits to get a starting armor of 43 is safer. Perhaps it's better to stock up more USER credits before attempting this. Do note that should the player end up completing mission X with armor mods remaining, they are not refunded as credits. Also, just like infinite armor in Trial or Training mode, there is no visual indication what the armor amount is except for the green armor color that appears when total armor is above 3.
Thus, it is up to the player's confidence and risk tolerance to add more armor using Assisted 1CC. Everyone will be able to get all the achievements using this feature. Similar to Auto Bomb, using an Assisted 1CC disqualifies the run from online leaderboards. There is also no mission clear bonus when armor is above 3. Players should turn off these assists when they are skilled enough and play the high score end game.
Now go get that 1CC!